Date: Wed, 31 Aug 2005 07:42:02 -0700 (PDT) From: User Tomdean <tomdean@speakeasy.org> To: ticso@cicely.de Cc: freebsd-usb@freebsd.org Subject: Re: Ucom/Uftdi Thru-put Message-ID: <200508311442.j7VEg2Nu006607@asus.tddhome> In-Reply-To: <20050831101526.GX37930@cicely12.cicely.de> (message from Bernd Walter on Wed, 31 Aug 2005 12:15:27 %2B0200) References: <200508202157.j7KLv1GF005017@asus.tddhome> <20050826112422.GY37930@cicely12.cicely.de> <200508301751.j7UHpCt8000858@asus.tddhome> <200508302100.12140.hselasky@c2i.net> <200508302046.j7UKklqR000628@asus.tddhome> <20050831101526.GX37930@cicely12.cicely.de>
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I changed the input buffer size. The read reported 382 bytes. The
buffer is 6*(4*16)==384 bytes long. On the scope I see 6 distinct
groupings in the USB data stream. Looks like ucom/uftdi, or something
up the chain, is using 64 bytes anyway. Every 64 bytes, there seem to
be 2 bytes not from the data stream. Uftdi.c subtracts 2 from count,
giving 382 bytes.
tomdean
/*
* These are the maximum number of bytes transferred per frame.
* The output buffer size cannot be increased due to the size encoding.
^^^^^^
*/
#define UFTDIIBUFSIZE 384
#define UFTDIOBUFSIZE 64
I sent all 'a' == 0x61. Using gdb,
(gdb) p/x buf
$5 = {0x61616161 <repeats 15 times>, 0x60316161,
0x61616161 <repeats 15 times>, 0x60316161, 0x61616161 <repeats 15 times>,
0x60316161, 0x61616161 <repeats 15 times>, 0x60316161,
0x61616161 <repeats 15 times>, 0x60316161, 0x61616161 <repeats 15 times>,
0x6161,
^^^^ 382 bytes ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
0x0 <repeats 53 times>, 0x28052842, 0x0, 0x0, 0x0, 0x280695d8, 0xe8,
0x2813bda4, 0xbfbfe11c, 0x28052d83, 0xe8, 0x0, 0x2813c000, 0x14000,
0x28070100, 0x280695d8, 0x2813bda4, 0x28052d61, 0x28070100, 0x0, 0xe8,
0x28052d42, 0x280695d8, 0xbfbfe170, 0xbfbfe15c, 0x280527c1, 0xe8, 0x14000,
0x3, 0x1012, 0xffffffff, 0x280695d8, 0xbfbfe1cc, 0x28052428, 0x280695d8,
0x0, 0xbfbfe1cc, 0x28069bd4, 0x28069bf4, 0x2806f020, 0x0, 0x0, 0x25c, 0x3,
0x28137000, 0xc6000, 0x0, 0xda000, 0x28076000, 0x0, 0x0, 0x0, 0x28069c14,
0x2804e81a, 0x11, 0x0, 0x280701a0, 0x280695d8, 0x280509a9, 0x280695d8,
0xbfbfe44c, 0x2804f785, 0x28070100, 0x0, 0xbfbfe3d4, 0x2804f599, 0x0, 0x0,
0x0, 0x6, 0x0 <repeats 27 times>, 0x28059cca, 0xc5, 0x0, 0x0, 0x8000, 0x3,
0x1002, 0xffffffff, 0x0, 0x0, 0x0, 0x0, 0x280541ce, 0xc5, 0x280695d8,
0xbfbfe2dc, 0x28052c98, 0x0, 0x8000, 0x3, 0x1002, 0xffffffff, 0x0, 0x0,
0x2805296a, 0x0, 0x0, 0x1000, 0x28050e72, 0x28089994, 0x28089994,
0xbfbfe30c, 0x28050df6, 0x2, 0x280857b4, 0xbfe30c, 0x280695d8, 0x28072020,
0x0, 0xbfbfe32c, 0x28050da1, 0x28089994, 0x9a6322b, 0x28070100, 0x0...}
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